In the manufacturing process of semiconductor devices, there is performed a photolithographic process including forming of a resist film by applying a resist to a front surface of a semiconductor wafer (referred to as “wafer” herebelow) as a substrate, exposing the resist film, and developing the exposed resist film to form a resist pattern. In recent years, forming of a resist film with the use of an inorganic resist containing a metal has been considered, because of a high resolution of a resist pattern that is exposed by using extreme ultraviolet (EUV), and a high etching resistance in an etching step succeeding to the photolithographic process. In addition, in order to improve the exposure sensitivity by generating a larger amount of secondary electrons upon exposure, adding a metal to an organic resist is also considered.
When a metal adheres to an unintended portion of a wafer during a manufacturing step of a semiconductor device, electric properties of the semiconductor device is severely affected. Thus, such a metal adhesion should be strictly avoided. However, when a resist film containing a metal is developed, as described above, there is a possibility that a developer containing a dissolved resist flows from a front surface of a wafer to a peripheral end surface of the wafer and a peripheral portion of a rear surface of the wafer. In this case, these portions are contaminated with the metal. When a contaminated portion of the wafer comes into contact with a wafer processing apparatus, such as an etching apparatus and/or a wafer transfer mechanism, another wafer that is to be transferred and processed after this wafer may be contaminated with the metal through the processing apparatus and the transport mechanism. Namely, cross contamination may possibly occur. Although Japanese Patent Laid-Open Publication JP2013-062436A describes a technique in which a chemical liquid is supplied to a peripheral part of a wafer so as to form an annular film, the technique cannot solve the aforementioned problem.